principles of vid tech unfinished
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Principles ofVideo technology
KGV BTEC MEDIA
There are 3 main standards in use around the world.
P A L N T S C S E C A M
Each one is incompatible with the other.
For example, a recording made in the France could not be played on an American VCR or DVD player.
If you or your clients view video tapes or DVD's that are from other regions, you must first convert the tape or disc to or from the foreign television standard.
The system used in America & Canada is called "NTSC". Western Europe and Australia use a system called "PAL", and Eastern Europe and France use "SECAM". Without standards conversion, it is impossible to view a video program that is recorded in a foreign country without first converting it..
Television Standards: Analogue Systems
Television Standards: Analogue Systems
Frames - all the lines of definition
Fields - the lines which are shown at any one time
Horizontal resolution is limited by bandwidth; different places established different limits
Interlacing - The system whereby only half of the lines are seen at a time (eg 1080i)
Progressive - the system whereby all the lines are seen at once (eg 1080p)
Television Standards: Analogue Systems
Television Standards: Component and Composite Video Signals
What do ‘component’ and ‘composite’ mean?
Three cables, each with RCA plugs at both ends, are often used to carry YPbPr analog component video
In home applications, the composite video signal is typically connected using an RCA jack (phono plug), normally yellow. It is often accompanied with red and white connectors for right and left audio channels respectively. BNC connectors and higher quality coaxial cable are often used in professional television studios and post-production applications. BNC Connectors were also used for composite video connections on early home VCRs, often accompanied by either phono connector(s) or a 5-pin DIN connector for audio.
In Europe, SCART connections are often used instead of RCA jacks (and to a lesser extent, S-Video), so where available, RGB is used instead of composite video with computers, video game consoles, and DVD players.
On consumer products a yellow RCA connector is typically used for composite video.
Both ANALOGUE systems
Television Standards: Component and Composite Video Signals
ANALOGUE OPTIONS
DVI - Digital Video Interface
HDMI - High Definition Multimedia Interface
Television Standards: Component and Composite Video Signals
What’s best - DVI or Composite or HDMI?
VGA - Video Graphics Array
(Analogue)
Television Standards: Component and Composite Video Signals
HDMI DVI
Digital
Up to 1920*1200
Audio (8 channels)
BluRay support
Analogue or digital
Up to 1920*1200
No audio
No BluRay support
Television Standards: High Definition
To put the 720 or 1080 lines into perspective, televisions of the past had 480 lines. Since more lines means a better picture then that alone shows why the HDTV has a nicer picture than an analog TV.
More lines is nice but don't forget about the 'p' and 'i' in the 720p, 1080i and 1080p. The letter is an abbreviation for the type of scan the TV uses -- 'p' stands for progressive and 'i' stands for interlaced.
Progressive scan is better than interlaced because it processes the images twice as fast. This faster scan rate produces better clarity and color in the on-screen picture.
The difference between 720p and 1080i is minimal but the TV industry is using 720p more than 1080i. So, buying a 720p HDTV is recommended over a 1080i HDTV.
As far as 1080p, there is no doubt that 1080p is the best resolution on the market. However, there is little to no difference in picture quality between a 1080p and 720p at the 32" and below screen size.
Television Standards: Aspect Ratio
More info here
• 1.33:1 A standard television set; roughly equivalent to 4:3.
• 1.37:1 Referred to as the academy aspect ratio. The standard for films shot before the mid-1950s.
• 1.66:1 A bit wider than a standard TV, but not by much.
• 1.78:1 The dimensions of a widescreen television set; roughly equivalent to 16:9.
• 1.85:1 Popular aspect ratio for many movies.
• 2.35: Another popular aspect ratio for movies.Pan and Scan versus Widescreen
Television Standards: Aspect Ratio
We can change aspect ratio using an ANAMORPHIC lens which
basically squeezes the image.
Television Standards: Aspect Ratio
Broadcast Systems: Terrestrial, Digital,
Satellite
The basics of digital television
Broadcast Systems:Cable, Internet,
On-demand
Digital Editing: Hardware
1. WHAT ARE WE DOING WHEN WE EDIT DIGITALLY?
2. Digital editing:
3. file types;
4. file size;
5. compression;
6. system compatibility;
7. hardware;
8. software;
9. data transfer;
10. file management
Digital Editing: Software